Motor-controller.



W. B. LUCAS.

MOTOR CONTROLLER.

urmoumn FILED um 7, 1910.

Patented Mar. 31, 1914.

2 SHEETS-SHEET 1.

, W. B. LUCAS.

MOTOR CONTROLLER.

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WILLIAM. is. LUCAS, or cnrcaco, rumors.-

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Specification of Letters Intent.

Application filed January 7, 1910. Serial No. 536,865.

Patented Mar. 31, 1914.

To all whom it may concem Be it known that I, WILLIAM B. Lucas, a citizen of the United States of America,

and a resident of Chicago, county of Cook,

cuit with the motor controller.

State of Illinois, have invented certain new and useful Improvements in Motor-Controllers, of which the following is a specification. l

The main objects of this invention are to provide an improved form of motor controller particularly adapted for the purpose of automatically reduclng the startlng resistance in the motor circuit; to provide an improved mechanism capable of being controlled by the rotation of the rotor and adapted to positively insure the change of resistance required for the variation of speed of'the rotor; to provide an improved contruction whereby injury to the motor controller through failure to cut in res stance is practically impossible; to provide an improved construction of the contact devices to form a channel for containing the operating liquid; to provide improved means for reducing the starting resistance at equal speed intervals and to provide improved means for adjusting the cut-out intervals to conform to the speed characteristic of the motor controller.

A specific construction embodying this invention is illustrated in the accompanying drawings, in which Figure 1 is a transverse section of a motor controller constructed according to this invention, the position of the liquid when at rest bein shown by full lines and different ositlons of the liquid under varying conditions being indicated by dotted lines, the controlling resistance being shown diagrammatically. Fig. 2 is a longitudinal section partly broken away on the line A-A of Fig. 1, showing a method of securing the rotating shell to the shaft on the mountin of the brush holders. The line BB in icates the plane of sectionof Fig. 1. Fig. 3 is a diagrammatic representation of the motor windings as connected in cirdetail partlysectional showing the method of mounting the brush holder on its support. Fig. 5 is a detail ofthe brush holder nut.

In the construction shown, a series of equally spaced and insulated contact devices or segments 1 form an annular wall or rotatable shell 2. Each segment 1 extends from the inner face of the shell to the outer.

Fig. 4 is a- ;face of the shell, and each segment 1 is pro- FVldPd at each end with two projections 3, 3 which extend toward the center of the shell, forming with the insulating material a channel for supporting a conducting liquid ,5 whlch is spread circumferentially when the shell is rotated.

A series of brushes 6 engage the outer surface pf the shell 2 and are spaced at increasing intervals beginning with the segments which are out of contact with the edges of the liquid 5 when the shell is at rest and ending with the brush'at the highest point on the shell. The brushes are connected by conductors 7 and in the form shown each of the conductors 7 represents a resistance connected between adjacent brushes 6, symmetrically placed brushes on the same horizontal plane are cross-connected with low resistance conductors 8 and 8 The rotatable shell 2 is mounted on the motor shaft 9. The center of the end member 10 is tapped to engage the threads of a bolt 11 which carries a second end member orplate 12 and holds the segments in position by wedge end compression as is usual in commutator construction. Insulating material 13 is placed between the compres sion surfaces of the segments and the compression wedges 14, 14.- and compressible insulating material 13 is also placed between the projections'3, 3 and end members 10 and 12. The inner surface of each segment is provided with corrugations 15 between the projections 3 and 3 to increase the contact surface with'the liquid 5.

The brush holders 16 are held in position by means of a slotted brush holder ring 17 supported on brackets 18 which are in turn bolted to the motor shaft bearing 19. The individual brush holders 16 are secured to the brush holder ring 17 by means of a fillister head screw 20 which is embedded in the insulated side of'the brush holder 16, and engages a nut 21. A spring 22 normally urges the brush in the brush holder into contact with the outer surface of the shell. The resistances 7 inserted between the brushes are connected in the circuit by connecting one armature lead L to the two lower brushes. From the two lower brushes the current divides and passes in parallel through the resistance to the the next higher brushes which are joined by the cross-connecting wire 8. In a similar manner, the current is led through the next higher resistances to the pair of brushes which are joined by the cross-connecting wir'e 8 to the upper brush which is connected to the armature lead L.

In operation, the resistances are connected in the circuit with the armature or rotor, and the rotatable shell with the contained conducting liquid is driven by the motor shaft. When the motor is at rest, all the resistance is in circuit with the armature. When the main circuit is closed, and the motor accelerates, the resistance is gradually short-circuited since both friction and centrifugal force will tend to spread the conducting liquid in the channel formed by the inner faces of the segments. Just before the motor reaches normal speed, the liquid will reach the top of the shell and be spread out in a continuous ring short-circuiting all of the segments and thereby cutting out all of the startin resistance. In case the current supply fails, the motor will stop and the liquid will return to the rest position, and a second closing of the main circuit cannot injure the motor since the normal rest position is always the normal starting position.

When a change in the starting characteristic is desired, the brushes can be shifted on the brush holder ring to effect an earlier -or a delayed short-circuiting of the individual resistances. The inwardly extending parts at-the ends of the segments hold the liquid in the channel formed by these projections and prevent centrifugal pressure of the liquid on the wedge compression joints.

Although but one specific embodiment of this invention is herein shown and described, it will be understood that numerous details of the construction shown may be altered or omitted, within the scope of the following claims, without departing from the spirit of this invention.

I claim 1. In a motor controlling device, a. rotatable shell comprising an annular wall of conductin segments insulated from each other, end members supporting said wall, sliding contacts engaging the external surface of said wall, resistances connected between said sliding contacts, and a mass of conducting material supported in said shell and adapted to spread circumferentially, thereby short-circuiting said segments when said shell is rotated.

12. In a motor controlling device, a rotatable shell comprising an annular wall of conducting segments insulated from each other, end members supporting said wall, sliding contacts in circuit with the motor and engaging the external surface of said wall, resistances connected between said sliding contacts, and a mass of conducting mate rial supported in said shell and adapted to spread circumferentially, thereby short-circuitmg said resistances when said'shell is rotated.

contact with said segments and a apted to automatically short-circuit said segments through the rotation of said motor rotor.

4. In a motor controlling device, a plurality of segments insulated from each other and secured together to form a hollow shell,

the inner and outer faces of said segments being substantially true with the axis of said shell, outer conductors having sliding contact with the outer faces of said segments,

resistances connecting said outer contacts,

and a flowing conductor having moving contact with the inner faces of said segments and adapted to automatically short-circuit said segments when the speed of the motor is increased.

5. In a motor controlling device, the combination with the motor, of a rotatable shell comprising a series of segments of conducting material insulated from each other and disposed substantially parallel with the axis of rotation, end members supporting said insulated segments and forming with said segments a substantially liquid-tight hollow shell, brushes bearing on the outer surface of said. segments, resistances connecting said brushes, a liquid conductor supported by the inner surface of said segments and adapted to automatically short-circuit said brushes when the speed of the motor is accelerated and to open said short-circuit when the speed of the motor is diminished.

6. In a motor controlling device, the combination with the mot-or of a rotatable shell comprising a series of segments of conducting material insulated from each other, end members supporting said segments, said segments having inwardly extending parts at their opposlte ends to form an annular channel for confining a liquid and preventing it from exerting centrifugal pressure at the joint between said end members and said segments, brushes bearing on the outer surface of said segments, resistances connecting said brushes, and a liquid conductor supported on the inner surface of said segments and adapted to automatically short-circuit said brushes when the speed of the motor is accelerated.

7. In a motor controlling device, the combination with the motor of a rotatable shell comprising a series of segments of conducting material insulated from each other, end members supporting said segments, a conducting liquid supported in contact with the inner surface of said segments, said segments being corrugated onthe inner surface to increase the surface contact, brushes bearing on the outer surface of said segments, and resistances" connected between said brushes, said conducting liquid being adapted to spread circumferentially, thereby shortcircuiting'said segments when said shell is rotated.

8. In a motor controlling device, the combination with a motor rotor of a plurality of segments insulated from each other and secured together to form a shell having a chamber, means for supporting said segments, brushes having sliding contact with said segments, resistances connectlng said brushes, and a flowing conductor in said chamber in contact with said segments and adapted to automatically short-circuit said segments through the rotation of said rotor.

9. In a motor controlling device, the combination with a motor rotor of a plurality of segments insulated from each other and secured together and shaped to forma shell having therein a channel, means for supporting said segments, brushes spaced at varying angular intervals about the axis of rotation and having sliding contact with said segments, resistances connecting said brushes, and a flowing conductor in said channel in contact with said segments and adapted to automatically short-circuit said segments through the rotation of said rotor.

'10. In a motor controlling device, the combination with a motor rotor of a plurality of segments insulated from each other and secured together to form a shell having a chamber, means for supporting said segments, brushes spaced at successively 1ncreasing angular intervals about the axis of rotation and having sliding contact with said segments, resistances connecting said brushes, and a flowing conductor in said chamber in contact with said segments and adapted to automatically short-circuit said segments through the rotation of said rotor.

. 11. In a motor controlling device, the combination with a motor rotor of a plurality of segments insulated from each other and secured together and shaped to form a. shell having therein a channel, means for supporting said segments, brushes symmetrically arranged with respect to a vertical center line and spaced at successively increasing angular intervals at each side of said line and having sliding contact with said segments, resistances connecting said brushes, and a flowing conductor in said channel in contact with said segments and adapted to automatically short-circuit said segments through the rotation of'said rotor.

12. In a motor controlling device, the combination with a motor rotor. of a plurality of segments insulated from each other and secured together and forming a shell having therein a channel, means for supporting said segments brushes having sliding contact with said said brushes, and a flowing conductor in said channel in contact with said segments and'adapted to automatically short-circuit said segments through the rotation of said rotor, said brushes being so disposed and said resistances being so proportioned that the amount of resistance short-circuited varies with the speed.

13. In a motor controlling device, the combination with a motor rotor of a plurality of segments insulated from each other and secured together and forming a shell having therein achannel, means for supporting said segments, brushes "having sliding contact with said segments, resistances connecting said brushes, and a flowing conductor in contact with said segments and adapted to automatically short-circuit said segments through the rotation of said rotor, said brushes being relatively adjustable to different angular spaces with respect to each other.

14. In a motor controlling device, the combination with a motor of a pluralityof segments insulated from each other and secured together and forming a shell having therein a channel, a member supporting said segments, a brush holder ring, brush holders mounted on said ring and adjustable circumferentially thereon, brushes in said brush holders bearing on said segments, a flowing conductor supported in said channel in contact with said segments and adapted to automatically short-circuit said segments through the rotation of said motor.

15. In amo-tor controlling device, the combination with a motor of a plurality of segsegments, resistances. connectinging on said segments, resistance connecting said brushes,a flowing conductor supported in said channel in contact with said segments and adapted to automatically short-circuit said brushes through the rotation of said motor.

16. In a motor controlling device, a rotatable shell having a cavity supporting a liquid and comprising an annular series of transversely disposed contact devices insulated from each other and having inwardly and outwardly facing contact surfaces, stationary brushes bearing on said shell and adapted to successively bear upon the severalcontact devices when the shell rotates, and resistances connected between said brushes, said liquid being adapted to shortcircuit said contact devices through the ro- 17. In a motor controlling device, a rotatable shell having a cavity supporting a liquid and comprislng an annular series of transversely disposed contact devices insulated from each other and having inwardly and outwardly facing contact surfaces, stationary brushes adjustable circumferentially with respect to said shell bearing on said shell and adapted to successively bear upon the several contact devices when the shell rotates, and resistances connected between said brushes, said liquid being adapted to short-circuit said contact devices through the rotation of said shell,

18. In a motor controlling device, a rotatable shell having a cavity therein for supporting a liquid, a series of transversely disposed contact bars in the wall of said cavity and each having a contact surface on the outer periphery of said shellin peripheral alinement, brushes spaced apart peripherally and arranged to bear on said contact surfaces successively when the shell rotates, a resistance in circuit with the motor and connected to said brushes, and a liquid conductor in said cavity adapted to short-circuit said resistances through the rotation of said shellr 19. In a motor controlling device, a 1'0- tatable shell having a cavity therein for supporting a liquid, a series of transversely disposed contact bars in the wall of said cavity and each having a contact surface on the outer periphery of said shell in peripheral alinement, brushes adjustable circumferentially and arranged in alinement 20. In a motor controlling mechanism, I

the combination of rotatable commutator segments forming a receptacle within them, a flowin conductor in such receptacle, symmetricalLy disposed brushes outside of the receptacle on opposite'sides thereof and in contact with such segments, and conductors directly connecting similarly placed ones of such brushes. 1

21. In a motor controlling mechanism, the combination of a rotatable cylindrical receptacle, conductors disposed in a peripheral series on its inner surface and communicating electrically with the exterior of said receptacle, a flowing conductor held in said receptacle, brushes arranged in a peripheral series on the outer surface of the receptacle and substantially symmetrically disposed on opposite sides thereof for deliver ing currentto said conductors, and external resistances connected between the said brushes for efi'ecting control of the motor for either direction of rotation.

Signed at Chicago this 26th day of November, 1909.,

PHILIP B. Woonwonon, MARY M. DILLMAN. 

